在我的c#程序中没有得到预期的输出,文件中写入了错误的日期格式
本文关键字:文件 输出 格式 日期 错误 程序 我的 | 更新日期: 2023-09-27 18:26:19
我编写的代码不应该接受错误的日期格式。Mine显示无效的选择,但在文本文件中存储了不正确的日期格式。如果日期格式不正确,则不应将其存储在文本文件中。
using System;
using System.Collections;
using System.IO;
using System.Globalization;
class FunWithScheduling
{
public void AddView()
{
FileStream s = new FileStream("Scheduler.txt",FileMode.Append,FileAccess.Write);
StreamWriter w = new StreamWriter(s);
Console.WriteLine("Enter the Name of the Person To Be Met:");
string Name = Console.ReadLine();
Console.WriteLine("Enter the Date Scheduled For the Meeting:");
string Date = Console.ReadLine();
DateTime date;
if(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid Choice");
}
Console.WriteLine("Enter the Time Scheduled For the Meeting:");
string Time = Console.ReadLine();
string line = Name + " "+ Date +" " + Time;
w.WriteLine(line);
w.Flush();
w.Close();
s.Close();
}
static void Main()
{
FunWithScheduling a = new FunWithScheduling();
a.AddView();
}
}
这个修改后的程序不起作用。While永远不会结束,并且不会接受正确的日期格式,也不会保存在文本文件中。
不允许我使用字符串生成器。
using System;
using System.Collections;
using System.IO;
using System.Globalization;
class FunWithScheduling
{
public void AddView()
{
FileStream s = new FileStream("Scheduler.txt",FileMode.Append,FileAccess.Write);
StreamWriter w = new StreamWriter(s);
Console.WriteLine("Enter the Name of the Person To Be Met:");
string Name = Console.ReadLine();
Console.WriteLine("Enter the Date Scheduled For the Meeting:");
string Date = Console.ReadLine();
DateTime date;
if(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid date format!");
while(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid Date Entered, please format MM-dd-yyyy");
Date = Console.ReadLine();
}
}
Console.WriteLine("Enter the Time Scheduled For the Meeting:");
string Time = Console.ReadLine();
string line = Name + " "+ Date +" " + Time;
w.WriteLine(line);
w.Flush();
w.Close();
s.Close();
}
static void Main()
{
FunWithScheduling a = new FunWithScheduling();
a.AddView();
}
}
您必须添加:
return;
之后:
Console.WriteLine("Invalid Choice");
同样最好将FileStream
和StreamWriter
初始化移动到条件检查之后:
using System;
using System.Collections;
using System.IO;
using System.Globalization;
class FunWithScheduling
{
public void AddView()
{
Console.WriteLine("Enter the Name of the Person To Be Met:");
string Name = Console.ReadLine();
Console.WriteLine("Enter the Date Scheduled For the Meeting:");
string Date = Console.ReadLine();
DateTime date;
if(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid Choice");
return;
}
Console.WriteLine("Enter the Time Scheduled For the Meeting:");
string Time = Console.ReadLine();
string line = Name + " "+ Date +" " + Time;
FileStream s = new FileStream("Scheduler.txt",FileMode.Append,FileAccess.Write);
StreamWriter w = new StreamWriter(s);
w.WriteLine(line);
w.Flush();
w.Close();
s.Close();
}
static void Main()
{
FunWithScheduling a = new FunWithScheduling();
a.AddView();
}
}
我建议您使用"else"语句来解决"Date"的问题。然后使用字符串生成器而不是+
来构建字符串。
我试图在这里帮助你,但我还没有通过编译器运行它。
using System;
using System.Collections;
using System.IO;
using System.Globalization;
using System.Text;
class FunWithScheduling
{
public void AddView()
{
FileStream s = new FileStream("Scheduler.txt",FileMode.Append,FileAccess.Write);
StreamWriter w = new StreamWriter(s);
var builder = new StringBuilder();
Console.WriteLine("Enter the Name of the Person To Be Met:");
string Name = Console.ReadLine();
builder.Append(Name);
Console.WriteLine("Enter the Date Scheduled For the Meeting:");
string Date = Console.ReadLine();
DateTime date;
if(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid Choice");
} else {
builder.Append(date.ToString("MMMM dd, yyyy"));
}
Console.WriteLine("Enter the Time Scheduled For the Meeting:");
string Time = Console.ReadLine();
builder.Append(Time);
w.WriteLine(builder.ToString());
w.Flush();
w.Close();
s.Close();
}
static void Main()
{
FunWithScheduling a = new FunWithScheduling();
a.AddView();
}
}
您也可以尝试类似的while语句,以强制用户输入正确的日期。
while(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date)){
Console.WriteLine("Invalid Date Entered, please format MM-dd-yyyy");
Date = Console.ReadLine();
}
//当输入的日期无效时,将日期设为空;它将不会存储在文本文件中。
if(!DateTime.TryParseExact(Date,"MM-dd-yyyy",
new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid Choice");
Date = "";
}
首先,是的,使用StringBuilder,而不是只使用字符串+,因为当你这样做时,字符串将乘以两个字符串的内存使用量,这意味着你有2个内存分配给2个分离的字符串,1个内存分配用于合并的字符串,这只是未来的一个提示。
你所需要做的就是要么做
StringBuilder sb = new StringBuilder();
sb.Append(Name);
if(!DateTime.TryParseExact(Date,"MM-dd-yyyy",new CultureInfo("en-US"),DateTimeStyles.None,out date))
{
Console.WriteLine("Invalid Choice");
}
else
{
sb.Append(Date);
}
然后当你向文件本身写入时,只需进行
w.WriteLine(sb.ToString());
当用户输入错误的日期时,您有两个选项:
- 关闭流并退出代码
- 要求用户通过指定格式重新输入日期
要关闭流并退出,您必须在之后添加以下代码:
Console.WriteLine("Invalid Choice");
w.Flush();
w.Close();
s.Close();
return;
和
要要求用户重新输入,直到他指定了正确的答案,请在以下代码后添加:
Console.WriteLine("Invalid Choice");
while(!DateTime.TryParseExact(Date, "MM-dd-yyyy", new CultureInfo("en-US"), DateTimeStyles.None, out date))
{
Console.WriteLine("Invalid Date Entered, please format MM-dd-yyyy");
Date = Console.ReadLine();
}